Sunday 6 September 2015

enhanced vegetation index

Recently ecologists endeavoured to take a more accurate census of the number of individual trees, as each comprises an arboreal habitat within its own branches and is also a part of a larger, contiguous network of the forest.
Taking to the woods with clipboards and questionnaires, researchers discovered that their previous estimates on the total, global tree population—relying mostly on satellite images that showed ground cover and calculating the percentages of wild and cultivated land, were off by almost a power of ten: instead of some four hundred billion leafy compatriots, there are some three trillion. The old methods did not take into account the shifting densities that the census-takers encountered in their surveys, and the demographic projections seem to be solid and rigorous—not just another model to be later prised apart. The findings are optimistic (forests are more robust in some parts of the world than they were a century ago) but we humans still are not good stewards of the environment and could prove to be an important point of departure for further sustainability studies and determining how much room is needed to grow and thrive.